At 05:37 PM 06/08/2000 +0800, Sim, CT (Chee Tong) wrote:
>Dear friends,
>
>Can I ask you some basic question, don't laugh at me :P if u just want to
>answer me one of the question, just help me .
>
>1) What is difference between ping and telnet? telnet is using port 23, how
>about PING? which port is that? I understand we can use the access-list to
>control whether a telnet session can be established, how about ping, Are we
>using the ip route command to whether PING traffic to pass thru?
Telnet is an application using tcp port 23.
Ping is another application using icmp (a special ip protocol), neither TCP
nor UDP is
involved. Ping uses ICMP packet type echo.
>
>2) We open a port in Firewall to let user can telnet to a server in remote
>site. Does it mean that we can ping to the server. If not, What should we
>do in order to let user can ping to the server?
No, you have to open ICMP echo and echo-reply for ping to work.
>
>3) What is mean by Multicast? I know there is a range of IP for Multicast?
>But when we need it?
>
I think you are talking about layer 3 multicast. A special range of ip address
224.0.0.0-239.0.0.0 are reserved for IP multicasting. For example, any devices
configured with 224.0.0.5 are OSPF desinated routers. If you want to send some
IP packets to those routers only, you can address the packet to that address.
Multicast is also used for multimedia traffic. You can even use it across the
Internet (MBONE). Multicast can be staticaly/dynaimcally routed. Popular
dynamic
routing protocols including IGMP, CGMP, PIM etc. AppleTalk also supports
multicasting.
Jim Xie
>
>Thanks
>
>Sim Chee Tong
>
>
>
>
>
>
>==================================================================
>De informatie opgenomen in dit bericht kan vertrouwelijk zijn en
>is uitsluitend bestemd voor de geadresseerde. Indien u dit bericht
>onterecht ontvangt wordt u verzocht de inhoud niet te gebruiken en
>de afzender direct te informeren door het bericht te retourneren.
>==================================================================
>The information contained in this message may be confidential
>and is intended to be exclusively for the addressee. Should you
>receive this message unintentionally, please do not use the contents
>herein and notify the sender immediately by return e-mail.
>
>
>==================================================================
>
>
>___________________________________
>UPDATED Posting Guidelines: http://www.groupstudy.com/list/guide.html
>FAQ, list archives, and subscription info: http://www.groupstudy.com
>Report misconduct and Nondisclosure violations to [EMAIL PROTECTED]
___________________________________
UPDATED Posting Guidelines: http://www.groupstudy.com/list/guide.html
FAQ, list archives, and subscription info: http://www.groupstudy.com
Report misconduct and Nondisclosure violations to [EMAIL PROTECTED]
